Hydraulic controlling system



April 18, 1939. FVBROW 2,154,832

HYDRAULI C CONTROLLING SYSTEM Filed Oct. 14; 1955 5 Sheets-Sheet 1 April 18, 1939. F, v. BROWN HYDRAULIC CONTROLLING SYSTEM 3 Sheets-Sheet 2 Filed Oct. 14, 1955 April 18, 1939. F. v. BROWN 2,154,832

HYDRAULIC CONTROLLING SYSTEM Filed oci. 14, 1935 5 Sheets-Shet s W- muumlmun 1h I I F Will a .Zk ae 7; 2'2 I ZZ/Zea? 4B1 mica/6 time] Apr. 18, 1939 UNITED STATES PATENT OFFICE mnamc' con'moumc srs'rnm Francis Victor Brown, London, England, assignor to Automotive Products Company Limited, London, England Application October 14, 1935, Serial No, 45,002

'lClaims.

ber of devices to be operated or controlledlhydraulically, but also in respect of the actual work done by the hydraulic controls.

This result is obtained in accordance with the invention by a method of operating a hydraulic controlling system, which consists in providing a mechanically driven pump and a manually operated source of liquid pressure for alternative actuation of hydraulically controlled elements, such as hydraulic jacks. As a modification the invention provides a method consisting in utilizing for the purpose of controllingthe flow of fluid from a mechanically driven pump, a member which itself constitutes the operating means of a manually actuated pump.

Thus, in a hydraulically controlled system in which liquid under pressure in a closed circuit serves to transmit power or movement, according to the invention pressure-producing means are provided comprising in combination a mechanically driven pump and a manually operated pump, either of which can be used independently of the 0 her.

As a further feature, in a hydraulic controlling system in which pressure is produced normally by a mechanically driven pump or equivalent, the output from which is controlled by a manually operated member, according to the invention said manually operated member is adapted also to actuate manually operated pumping means should the mechanically driven pump be inoperative. It will be. understood that the improved method, although particularly applicable to aircraft may be applied for other purposes, while, of course, the term manually operated is intended to cover all forms of actuation which are not mechanical, for example pedal actuation.

The improved system is preferably arranged so that no changing over operation is required for bringing the manual means into action, nonreturn valves or equivalent being employed 'so that either the mechanical or manual operation not shown in Figures 1 and 2, but in effect,

can be effected at will at any time.

One general form of system according to the invention is illustrated in the accompanying drawings in which Figure 1 is a diagram illustrating the layout 4 Figure 2 is a diagram corresponding to Figure 1 showing the position of the valves when the plunger of the jack is being moved to the left by the mechanically actuated pump;

Figures 3 and 3a collectively illustrate in frag- In Great Britain March 16, 1935 mentary sectional side elevation one construction of combined manual pump and controlling means;

Figure 4 is a sectional front elevation of the control valve incorporated in Figu e 3;

Figure 5 is a fragmentary front elevation showing the means employed for rendering inoperative either one or both of the bleeder valves of the manual pump; and

Figure 6 is a diagram to a reduced scale showing the pipe connections for the pump construction illustrated in Figures 3 to 5.

Referring firstly to Figures 1 and 2 in which the component parts of the preferred system are shown diagrammatically, it will be seen that the component parts comprise a reservoir 15,, a manual pump unit B with which is associated a selector valve unit C, a mechanically driven pump D and one or more hydraulic jacks E or other devices requiring to be controlled or actuated by fluid pressure.

The manual pump unit comprises briefly an outer casing l0 which is maintained full of liquid from the reservoir A by means of a pipe line, I I, said casing l0 being-fitted with four master cylinders i2, i3, i4 and I5 arranged substantially as described in British Patent No. 428,252 of May 9, 1935. Each of these cylinders is providedwith a piston, these being indicated at l6, i1, i8 and i9 and-being connected in pairs by bars 20 and 2|. Each piston includes a packing cup to the interior of the associated cylinder, but prevents return flow, as does the corresponding structure indicated in McDougall Patent No.

\ 2,004,078 granted June 4,,1935. For'actuating The upper end of'thi's handle carries a knob 25 which is arranged for rotation relative to thehandle 24 for the purpose of controlling a pair of push rods 26 and 21 associated with corresponding bleeder valves 28 and 29. The mechanical means employed for this purpose are rotation of the knob 25 in a clockwise direction when viewed from the top, causes the rods 26 and 21 to be moved to the left, thus allowing the bleeder valve 29 to engage its seating. When the knob 25 is in its normal or neutralposition both of the valves 28 and 29 are held off their seatings.

The bleeder valves 28 and 29 are arranged to control communication between the interior of the casing in which is, of course, under low pressure, and a pair of delivery chambers 30 and ill into which liquid is forced underv pressure by v the pistons II, I! and l8, l9 respectively when which yields to permit flow from the reservoir in the handle 24 is moved backwards and forwards 'will be forced along one of the service pipes for actuating the jack, while the liquid rejected at the other end of the master cylinder is returned to the casing l9 through the open bleeder valve. Thus the direction in which the knob 25 is initially rotated determines which way the pistons 31 of the jacks E are moved, and assuming said knob is turned so as to move the rods 26 and 21 to the left the bleeder valve 29 will be allowed to close, thus enabling liquid to be forced by the pistons l8 and I9 through corresponding delivery valves 38 and 39 into the service pipe 36 and the working chamber 34 of each of'the jacks E. At the same time the bleeder valve 28 is held open so that the discharge from the cylinders I2 and |3'me rely passes back into the casing ||l, while the liquid rejected by the contraction in the working space 33 of each of the jacks E also passes through the bleeder valve 28 into the casing l0. By rotating the knob 25 in the opposite direction the bleeder valve 28 is allowed to close, and oscillatory movement imparted to the handle 24 will then cause the piston 31 of the jack E to be moved in the opposite direction.

Associated with the spindle 23 is a valve rocker indicated at 40, which serves to actuate the selector valve C by means of a pair of plunger rods 4| and 42 which, in the neutral position of the rocker 40, hold a pair of balls 43 and 44 off their seats. As will. be seen in Figure 1 both branches 45 and 46 of the selector valve C are fed by'the delivery pipe 11 of the mechanically operated pump D and serve to deliver liquid under pressure through non-return valves 48 and 49 respectively into the service pipes 35 and 36 respectively. The inlet of the pump D is fed by means of a pipe 50- connected with the pipe II or with the casing Ill. The pump D,'which can be driven from the aircraft engine,'an electric motor, a propeller in the slip-stream or any other mechanical source of power, can be. arranged to operate continuously, and with the handle 24 and knob 25 in their neutral positions will merely serve to circulate liquid past both valves 43 and 44 and thence into the casing |0 from which it is in turn withdrawn through the pipe 50. If, however, it is required to move the piston 31 of the jack or jacks E to the left, i. e. charge the Working space 34 with liquid under pressure as shown in Figure 2, the knob 25 is rotated clockwise, thus allowing the bleeder valve 29 to close as hereinbefore described. The handle 24 is also moved to the right and retained in that position so that the leit hand end of the rocker 40 is raised and the push rod- 4| thus allows the valve 43 to close. This prevents liquid from the pump D passing through the open bleeder valve 28, andit is, therefore, delivered through the valve 44 into the pipe 36 from which it cannot escape except into theworking space 34. At the same time fluid rejected from the working space 33 of the jack or jacks E flows past the open bleeder valve 28 into the casing l0. When movementof the jack piston 31 in the other direction is required, exactly the opposite pro-' cedure is adopted, the knob 25 being twisted anticlockwise so as to allow the bleeder valve 28 to close, and the handle 24 is moved to the left, thus allowing the valve 44 to close the passage 46 to prevent the flow of high pressure liquid delivered by the pump D. It will be seen that "when the handle 24 is oscillated for operating the pump B manually, the valves 43- and 44 are alternately allowed to close but this does not affect the working of the pump B owing to the provision of the non-return valves 48 and 49.

One, constructional example of pump unit B arranged to work in accordance with the foregoing description is shown in Figures 3, 4 and 5. The pump casing I0 is fed with liquid from the reservoir A through a pipe connection 5| shown with a tubular extension 52 arranged to serve as a bearing for the spindle 23, which latter carries at its inner end a rocker 22 connected at its extremities with the connecting bars 20 and 2| respectively. The spindle 23 is tubular, and is fitted internally with an axially movable control member 53 which is grooved circumferentially at 54 so as to produce a toothed rack engaging with teeth upon a rod 55, the latter being thus rotated about its axis by endwise movement of the control member 53. This movement is brought about by the engagement of a pinion 56 with a rack 51 carried by the member 53, said pinion 56 being formed on the end of a rod ,58 which extends within the operating handle 24 and terminates in the knob 25. Thus reciprocatory movement imparted to the handle 24 is transferred by the spindle 23 to the rocker 22, and thence to the various pistons, and the controlling member 53 also shares this movement, without, however, affecting the angular position of the rod 55.

The action of this spindle is shown more clearly in Figure 6, from which it will be seen that the rod 55 is located against axial movement by a ball 59 provided at each end. The rod 55 is also encircled by a pair 'of collars 60 and 6| formed with cam surfaces 62 and 63 which engage with radial pins 64 and 65, said collars normally being forced inwards by means of helical compression springs 66 and 61. Ears 68 and 69 formed upon the collars 60 and Bi, respectively, are adapted to cooperate with the push rods 26 and 21, respectively, by which latter the bleeder valves 28 and 29 are normally held ofi their seats, when the rod 55 is in its neutral position as shown in Figure 5. Upon angular movement of the rod 55 taking place in either direction, however, one or other of 'the valves 28 and 29 is allowed to seat, thus permitting liquid pressure to be produced in 'the corresponding service pipe 35 .or 36.

The selector valve unit C is incorporated with the pump unit B as shown in Figure 3, and is actuated from the spindle 23 by the engagement of a transverse pin I0 upon the rocker 40 with corresponding notches formed in the end of the tube 23. The general construction of the selector valve is shown more clearly in Figure 4, said valve comprising a body H which is bored vertically to receive the push rods 4| and 42, resilient packing cups 12 being provided to prevent leakage of fluid. The rods 4| and 42 are normally urged in an upward direction by means of coiled springs I3 and are thus caused to remain in permanent engagement with the rocker member 40, although when the latter is in itsneutral position the lower ends of the push rods 4| and 42 hold the balls 43 and 44 off their -seats. The bores 14 and 15 are connected together by an intermediate hole I6, while apipe union Ha serves-to connect both with the delivery of the pump unit D by means of a pipe 11, as shown in Figure 6. The

as H in Figures 1 and 2, and is formed at its rear non-return valves 48 and 49 are also accommodated in the body I l, and are connected by means 01' banjo connections I8 and 19 with the service pipes 35 and 36 respectively.

When the mechanically driven pump is not working, the non-return valves 48 and 49 in the two branches of the selector valve 0 prevent the flow of liquid back into the mechanically driven pump D, and thus enable the manually operated pump B to be worked in the usual way by a repeated oscillatory movement of the handle 24 when once the correct bleeder valve has been allowed to close by angular movement of the knob 25 about its longitudinal axis.

The selector valve forms a compact unit which thus conveniently forms part of the manually operated pump.

The improved system according to the invention can be used for effecting a large number of mechanical operations such as applying and con.- trolling brakes, controlling and/or operating guns, while on an aircraft in particular it may, for example, be used for raising and lowering the undercarriage, raising and lowering the tail wheel, varying the position of aerofoil flaps, and for attaching or releasing any member which may be a part of or which may be carried by the aircraft. Where independent movement is required this can be obtained by the use of suitable valves for directing the pressure liquid, but in the preferred arrangement a separate manually operated pump is used for each individual part requiring independent actuation. Each of these pumps is'fitted with its own selector valve, but, of course, only one mechanically driven pump is required for feeding the whole of the selector valves, although more than one, mechanically driven pump can be used if desired.

What Iclaim is:-

1. The combination with a double-acting, liquid pressure, remote-control piston 31 and a cylinder in which said piston is reciprocable, of a reservoir I0 adapted tosupply liquid to either selected end of said cylinder, a pair of pipes 35, 36 connecting said reservoir with the opposite ends of said cylinder, so that one pipe serves as a delivery pipe with respect to said cylinder whilethe other pipe simultaneously serves as an exhaust pipe toreturn liquid to said reservoir, means including 'a set of valves 28, 29 controlling flow between said reservoir and said pipes, a second pair of pipes each of which communicates'with one of said first-named pair of pipes and each of which includes a valve 43, 44 controlling flow therethrough, mechanical means 24, 40, 41, 42 for holding both said last-named valves in flow-permitting position, means for closing one of said last-named valves when said mechanical means is shifted, and means 26, 21 movable during such a shifting or at any other time to cause movement of one of said first-named valves to a position cutting ofi communication between said reservoir and that particular one of said first-named pipes which has communication with that particular one of said second-named pipes whose valve is then in position permitting liquid flow therethrough.

2. The combination with a double-acting, liquid pressure, remote-control piston 31 and a cylinder 'in which said piston is reciprocable, of a reservoir l0 adapted to supply liquid to either selected end of said cylinder, a pair of pipes 35, 36 connecting said reservoir with the opposite ends of said cyl-- simultaneously serves as an exhaust pipe to return liquid to said reservoir, means including a set of valves 28,29 controlling flow between said reservoir and said pipes, a second pair of pipes each of which communicates with one of said first-named pairof pipes and each of which includes a valve 43, 44 controlling flow therethrough, mechanical means 24, 40, 4|, 42 for valve is then in position permitting liquid flow I therethrough, said mechanical means including a rocker arm having an actuating handle by which it may be swung about a transverse axis to produce operation of said second-named set of valves, and said handle being rotatable about the longitudinal axis of said rocker arm to control operation of the first-named set of valves.

3. The combination with a double-acting, liquid pressure, remote-control piston 31 and a cylinder in which said piston is reciproable, of a reservoir 10 adapted to supply liquid to either selected end of said cylinder, a pair of pipes 35, 36 connecting said reservoir with the opposite ends of said cylinder, so that one pipe serves as a delivery pipe with respect to said cylinder while the other pipe simultaneously serves as an exhaust pipe to return liquid to said reservoir, means including a set of valves 28, 29 controlling flow between said reservoir and said pipes, a second pair of pipes each of which communicates with one of said first-named pair of pipes and each of which includes a valve 43, 44 controlling how therethrough, mechanical means 24, 40, 4|, 42 for holding both said last-named valves in flow-permitting position, means for closing one of said last-named valves when said mechanical means is shifted, and means 26, 21 movable during such a shifting or at any other time to cause movement of one of said first-named valves to a position cutting off communication between said reservoir and that particular one of said first-named pipes which has communication with that particular one of said second-named pipes whose valve is then in position permitting liquid flow therethrough, said mechanical means including members operating individually upon each of said sets of valves to hold said valves in flow-permitting positions respectively, thereby allowing free circulation of liquid into and out of the reservoir,

flow between said reservoir and said pipes, a second pair of pipes each of which communicates with oneof, said first-named pair of pipes and each of which includes a valve 43, 44 controlling flow therethrough, mechanical means 24, 40, 4!,

42 for holding both said last-named valves in -flow-permitting position, means for closing one of said last-named valves when said mechanical means is shifted, and means 26, 21 movable during such a shifting or at any other time to cause movement of one of said first-named valves to a position cutting off communication between said reservoir and that particular one of said firstnamed pipes which has communication with that particular one of'said second-named pipes whose valve is then in position permitting liquid flow therethrough, said mechanical means including a rocker arm having an actuating handle adapted to swing said rocker arm about a transverse axis to produce operation of said second-named set of valves, and said handle being rotatable about the longitudinal axis of said rocker arm to control operation of the first-named set of valves, and in its neutral position operating to cause each of said first-named set of valves to be held in flowpermit'ting position, thereby allowing free circulatlon of liquid into and out of the reservoir without operative effect upon said piston.

5. The combination with a double-acting, liquid pressure, remote-control piston 31 and a cylinder in which said piston is reciprocable, of a reservoir l adapted to supply liquid to either selected end of said cylinder, a pair of pipes 35, 36

connnecting said reservoir with the opposite ends of said cylinder, so that one pipe serves as a delivery pipe with respect to said cylinder while the other pipe simultaneously selves as an exhaust pipe to return liquid to said reservoir, means including a set of valves 28, 29 controlling flow between said reservoir and said pipes, a second pair of pipes each of which communicates with one of Said first-named pair of pipes and each of which includes a valve 43, 44 controlling flow therethrough, mechanical means 24, 40, 4 I, 42 for holding both said last-named valves in flow-permitting position, means for closing one of said last- ,named valves when said mechanical means is shifted, and means 26, 21 movable during such a shifting or at any other time to cause movement or one of said first-named valves to a positioncutting off communication between'said reservoir and that particular one of said first-named pipes which has communication with that particular one of said second-named pipes Whose valve is then in position permitting liquid flow therethrough, said mechanical means including a rocker arm having an actuating handle adapted to swing said rocker arm. about a transverse axis to produce operation of saidsecond-named set of valves, and said handle being rotatable about the longitudinal axis of said rocker arm to control operation of the first-named set of valves, and in its neutral position operating to cause each of said first-named set of valves to be held in flow-permittingposition, thereby allowing free circulation of liquid into and out of the reservoir without operative efl'ect upon said piston, a third set 01 valves, each of which is adapted to open into one of said first-named pipes, and pump means mechanically linked with said rocker arm to produce pressure application to said third set Of valves in accordance with the direction of swing-of said rocker arm from its neutral position, and hence to produce movement of said piston in the desired direction.

6. The combination with a double-acting, liquid pressure, remote-control piston'3l and a cylinder in which said piston is reciprocable, of a reservoir I0 adapted to supply liquid to either selected end of said cylinder, a pair of pipes 35, 36 connecting said reservoir with the opposite ends of said cylinder, so that one pipe.serves as a delivery pipe with respect to said cylinder while the other pipe simultaneously serves as an exhaust pipe to return liquid to said reservoir, means including a set of valves 28, 29 controlling flow between saidreservoir and said pipes, a second pair of pipes each of which communicates with one of said first-named pair of pipes and each of which includes a valve 43, 44 controlling flow there through, mechanical means 24, 40, 4|, 42 for holding both said last-named valves in flowpermitting position, means for closing one of said last-named valves when said mechanical means is shifted, and means 26, 21 movable during such a shifting or at any other time to cause movement of one of said first-named valves to a position cutting off communication between said reservoir and that particular one of said firstnamed pipes which has communication with that particular one of said second-named pipes whose valve is then in position permitting liquid flow therethrough, said mechanical means including a rocker arm having an actuating handle by which it may be swung about a transverse axis to produce operation of said second-named set 01 valves, and said handle being rotatable about the longitudinal axis of said rocker arm to control operation of the first named set of valves, a third set of valves, each of which is adapted, to open into one of said first-named pipes, and pump means mechanically linked with said rocker arm to produce pressure application to said third set of valves in accordance with the direction of swing of said rocker arm from its neutral position, and hence to produce movement of said piston in the desired direction.

7. The combination with a double-acting liquid pressure, remote-control piston 31 and a cylinder in which said piston is reciprocable, of a reservoir l0 adapted to supply liquid to either selected end of said cylinder, a pair of pipes 35, 36 connecting said reservoir with the opposite ends of said cylinder, sothat one pipe serves as a delivery pipe with respect to said cylinder while the other pipe simultaneously serves as an exhaust pipe to return liquid to said reservoir, means including a set of valves 28, 29 controlling flow between said reservoir and said pipes, a second pair of pipes each of which communicates with one of said first-named pair of pipes and each of which includes a valve 43, 44 controlling flow therethrough, mechanical means 24, 40, 4|, 42 for holding both said last-named "valves in flow-permitting position, means for closing one of said lastnamed valves when said mechanical means is shifted, and means 26, 21 movable during 'such a shifting or at any other time to cause movement of one of said first-named valves to a position cutting off communication between said reservoir and that particular one of said first-named pipes which has communication with that particular one of said second-named pipes whose valve is then in position permitting liquid flow therethrough, a third set of valves, each of which isadapted to open into one of said first-named pipes, and pump means to produce pressure application to said third set of valves in accordance with the direction of movement of said mechanical means from its neutral position, and hence to produce movement of said piston in'the desired direction.

- FRANCIS VICTOR BROWN. 

